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Biomedical subjects

S Hirota

Publications and source records attributed to S Hirota.

At least 271 records · Page 15Linked to original sources
PubMed1986

Extrahepatic organs metabolism of inhaled trichloroethylene.

An extrahepatic circulation system for dogs was developed using a portal vein to right femoral vein bypass procedure. This system maintained nearly normal biochemical and physiological parameters, i.e. arterial blood pressure, heart rate, electrocardiogram, leukocyte and erythrocyte count, hematocrit, alkaline phosphatase, blood urea nitrogen, ammonia and creatinine, for 2 h. Thus, the system appears to be a valid technique for investigating extrahepatic metabolism. Dogs were exposed for 1 h to 500, 700 and 1500 ppm of trichloroethylene. Free-trichloroethanol, trichloroacetic acid and conjugated-trichloroethanol appeared in the blood and urine after 30 min of exposure. The amounts of metabolite formed by dogs with hepatic bypass were less than by similarly exposed dogs without hepatic bypasses, specifically 50-80%, 10% and 10-20% for free-trichloroethanol, trichloroacetic acid and conjugated-trichloroethanol, respectively. In addition, trichloroethylene exposure produced a smaller decrease in leukocyte counts in the hepatic bypass dogs than in the non-bypass dogs. This observation may indicate that the liver itself played some role in the elimination or increment of leukocyte counts in the blood.

Administration, Inhalation↗
PubMed1986

[Embolotherapy of hepatomas using ferromagnetic microspheres, its clinical evaluation and the prospect of its use as a vehicle in chemoembolo-hyperthermic therapy].

Ferromagnetic microembolization (FME) was applied to patients with hepatoma, using iron microspheres (30-50 mu), suspended in aqueous polysaccharide solution; dextran 40 (12%), sodium carboxymethyl-cellulose (2%) in saline solution. Hepatic arterial infusion of this agent was performed under external magnetic control to confine iron microspheres within the target organs. The therapeutic effect of this procedure on 44 patients with hepatoma was evaluated in relation to the stages of the disease, showing excellent, improved survival terms; survival rates calculated by Kaplan-Meier's method for patients with stage I to III hepatomas were 80% (1 year), 50% (2 years) and 30% (3 years). In order to extend the therapeutic effect of this procedure further, polysaccharide solution was also utilized as a carrier of anti-cancer agents. Serologic and histologic data in experimental animals showed evidence of prolonged release of Mitomycin from polysaccharide solution admixed, indicating its potential use as a method of chemo-embolization. In addition to this, we have also been developing the induction heating of the magnetic microspheres, introduced into the lesion by means of FME, to heat the lesion selectively. The procedure is still in the experimental phase. However, recent results strongly suggest the possibility of its clinical use. In conclusion, we consider FME to be one of the most reliable and potentially valuable methods for extending the capability of multidisciplinary treatment of hepatoma.

Animals↗